Agreed. She is definitely conflicted and it seems from her personality that she could be "redeemed" by those who are into that type of thing. Gale is the one I would suspect the most of having a hidden agenda and becoming "evil" by the end.
Agreed. My guess is that he doesn't have a bit of Mystrl but instead has a bit of the shadow weave in him and thus is helping Shar's mission of eliminating magic from the world. The question is does he know or not? Dupe or even better at deception than Shadowheart?
Sure, SH would need to dedicate her life to making up for her misdeeds but I'm guessing -- based on dialogue after Raphel -- that she's Patty Hearst only with torture and literal brain wipe. And the fact that she was first a victim changes the obligations to rehabilitate some.